Erythrocyte omega-3, omega-6 and trans fatty acids in relation to risk of preeclampsia among women delivering at Harare Maternity Hospital, Zimbabwe. (17/153)

We sought to examine the association between maternal erythrocyte omega-3, omega-6 and trans fatty acids and risk of preeclampsia. We conducted a case-control study of 170 women with proteinuric, pregnancy-induced hypertension and 185 normotensive pregnant women who delivered at Harare Maternity Hospital, Harare, Zimbabwe. We measured erythrocyte omega-3, omega-6 and trans fatty acid as the percentage of total fatty acids using gas chromatography. After multivariate adjustment for confounding factors, women in the highest quartile group for total omega-3 fatty acids compared with women in the lowest quartile experienced a 14% reduction in risk of preeclampsia (odds ratio 0.86, 95% confidence interval 0.45 to 1.63). For total omega-6 fatty acids the odds ratio was 0.46 (95% confidence interval 0.23 to 0.92), although there was suggestion of a slight increase in risk of preeclampsia associated with high levels of arachidonic acid. Among women in the highest quartile for arachidonic acid the odds ratio was 1.29 (95% confidence interval 0.66 to 2.54). A strong statistically significant positive association of diunsaturated fatty acids with a trans double bond with risk of preeclampsia was observed. Women in the upper quartile of 9-cis 12-trans octadecanoic acid (C(18:2n6ct)) compared with those in the lowest quartile experienced a 3-fold higher risk of preeclampsia (odds ratio = 3.02, 95% confidence interval 1.41 to 6.45). Among women in the highest quartile for 9-trans 12-cis octadecanoic acid (C(18:2n6tc)) the odds ratio was 3.32 (95% confidence interval 1.55 to 7.13). Monounsaturated trans fatty acids were also positively associated with the risk of preeclampsia, although of much reduced magnitude. We observed a strong positive association of trans fatty acids, particularly diunsaturated trans fatty acids, with the risk of preeclampsia. We found little support for the hypothesized inverse association between omega-3 fatty acids and preeclampsia risk in this population. Polyunsaturated fatty acids, particularly omega-3 fatty acids, were comparatively lower in Zimbabwean than among US pregnant women. Given the limited inter-person variation in omega-3 fatty acids among Zimbabwean women, our sample size may be too small to adequately assess the relation in this population.  (+info)

Effect of feeding systems on omega-3 fatty acids, conjugated linoleic acid and trans fatty acids in Australian beef cuts: potential impact on human health. (18/153)

The influence of feeding systems on the levels of functional lipids and other fatty acid concentrations in Australian beef was examined. Rump, strip loin and blade cuts obtained from grass feeding, short-term grain feeding (80 days; STGF) and long-term grain feedlot rations (150-200 days; LTFL) were used in the present study. The typical Australian feedlot ration contains more than 50% barley and/or sorghum and balanced with whole cottonseed and protein meals were used as feed for STGF and LTFL regimens. Meat cuts from 18 cattle for each feeding regimen were trimmed of visible fat and connective tissue and then minced (300 g lean beef); replicate samples of 7 g were used for fatty acid (FA) analysis. There was a significantly higher level of total omega-3 (n-3) and long chain n-3 FA in grass-fed beef (P< 0.0001) than the grain-fed groups regardless of cut types. Cuts from STGF beef had significantly reduced levels of n-3 FA and conjugated linoleic acid (CLA) and similar levels of saturated, monounsaturated and n-6 FA compared with grass feeding (P < 0.001). Cuts from LTFL beef had higher levels of saturated, monounsaturated,n-6 FA and trans 18:1 than similar cuts from the other two groups (P<0.01), indicating that increased length of grain feeding was associated with more fat deposited in the carcass. There was a step-wise increase in trans 18:1 content from grass to STGF to LTGF, suggesting grain feeding elevates trans FA in beef, probably because of increased intake of 18:2n-6. Only grass-fed beef reached the target of more than 30mg of long chain n-3 FA/100 g muscle as recommended by Food Standard Australia and New Zealand for a food to be considered a source of omega-3 fatty acids. The proportions of trans 18:1 and n-6 FA were higher (P<0.001) for both grain-fed beef groups than grass-fed beef. Data from the present study show that grain feeding decreases functional lipid components (long chain n-3 FA and CLA) in Australian beef regardless of meat cuts, while increasing total trans 18:1 and saturated FA levels.  (+info)

Production of butter fat rich in trans10-C18:1 for use in biomedical studies in rodents. (19/153)

Trans fatty acids are suspected to be detrimental to health, particularly to cardiovascular function. Trans fatty acids include a wide range of fatty acids, with isomers of C18:1, conjugated and non-conjugated C18:2 as major components. A vaccenic acid (trans11-C18:1) + rumenic acid (cis9,trans11-CLA)-rich butter has been shown previously to exhibit health beneficial effects, but less is known concerning another trans-C18:1 present in hydrogenated vegetable oil-based products and sometimes in milk fat, the trans10-isomer. The present experiment was conducted to produce butters from milk of variable fatty acid composition for use in biomedical studies with rodents, with the overall aim of evaluating the specific effect of trans10-C18:1 and trans11-C18:1 + cis9,trans11-CLA on cardiovascular function. Milks from lactating dairy cows fed two types of maize-based diets supplemented (5% of dry matter)--or not--with sunflower oil were collected, and used to manufacture butters either rich in trans10-C18:1 (14% of total fatty acids, 64.5% of fat content) or rich in trans11-C18:1 + cis9,trans11-CLA (7.4 and 3.1% of total fatty acids, respectively, 68.5% of fat content), or with standard fatty acid composition (70% of fat content). Additionally, total saturated fatty acid percentage was reduced by more than one third in the enriched butters compared with the standard butter. An understanding of the role of nutrition on milk fatty acid composition in cows allows for the production of dairy products of variable lipid content and composition for use in biomedical studies in animal models and human subjects.  (+info)

Trans fatty acids promote the growth of some Lactobacillus strains. (20/153)

Five Lactobacillus strains (2 L. gasseri, 2 L. plantarum and 1 L. reuteri) were cultured in modified MRS medium containing fatty acids (FAs) instead of Tween 80 for 24 h at 37 degrees C, to learn the effect of saturated and unsaturated FAs on the Lactobacillus growth. Free FAs included palmitic (16:0), palmitoleic (c9-16:1), stearic (18:0), oleic (c9-18:1), elaidic (t9-18:1), cis-vaccenic (c11-18:1), vaccenic (t11-18:1), linoleic (c9, c12-18:2), conjugated linoleic (c9, t11- and t10, c12-18:2), alpha-linolenic (c9, c12, c15-18:3), alpha-eleostearic (c9, t11, t13-18:3), eicosapentaenoic (20:5), and docosahexaenoic (22:6) acids. Among free FAs, oleic acid stimulated the growth of all Lactobacillus strains, whereas palmitoleic acid had almost no affect on the Lactobacillus growth. Saturated FAs such as stearic and palmitic acids inhibited or did not affect the Lactobacillus growth. Polyunsaturated FAs such as alpha-linolenic, eicosapentaenoic and docosahexaenoic acids strongly inhibited the Lactobacillus growth at 7.6 x 10(-4) m. Octadecenoic acids such as oleic, elaidic, cis-vaccenic and vaccenic acids remarkably promoted the growth of L. gasseri, regardless of the different double bond positions and configurations. When oleic or cis-vaccenic acid was incubated with L. gasseri, the FAs was transformed to cyclopropane FAs (methyleneoctadecanoic acids) after incorporation into the cells. On the other hand, trans FAs such as elaidic and vaccenic acids incorporated into the cells were not converted to another FAs. Conjugated linoleic and alpha-eleostearic acids having a trans double bond promoted the Lactobacillus growth. The growth of L. gasseri was also stimulated by trans-rich free FAs from hydrogenated canola and fish oils. These results showed that octadecenoic acid and trans FAs had strong promotion activities for the Lactobacillus growth due to their incorporation into membrane lipids.  (+info)

The conversion efficiency of trans-11 and trans-12 18:1 by Delta9-desaturation differs in rats. (21/153)

The present study evaluated and compared the efficiency of the conversion of t11 18:1 and t12 18:1 to their corresponding dienoic acids (c9,tn 18:2) and assessed whether differences due to gender existed in several tissues of rats. Three groups of 4-wk-old male and female rats were fed for 3 wk a diet supplemented with 0, 0.5, or 1% of a trans-octadecenoic acid isomer mixture (tOIM) containing t11 18:1 and t12 18:1 in equal proportion. t11 18:1 and t12 18:1 were incorporated in a tissue-specific manner, and the accrual was significant with increased dietary intake of these trans fatty acid (tFA) isomers. The t12 18:1 isomer was more readily incorporated into the rat tissues than the t11 18:1 isomer. From t11 and t12 18:1, the respective desaturase products, c9,t11 18:2 and c9,t12 18:2, were formed. The calculated conversion rates varied greatly among the tissues of the rats but they were consistently lower for t12 18:1 than for t11 18:1, suggesting that t12 18:1 is a poorer substrate than t11 18:1 for Delta9-desaturase. For both fatty acids investigated, the calculated conversion rates in decreasing order of conversion efficiency were: testes = kidneys > adipose tissue > ovaries > muscle > liver > heart. Overall, there were distinct differences in the conversion of t11 18:1 and t12 18:1, indicating that these 2 fatty acids are metabolized differently despite their structural similarities. Such metabolic differences in tFA accumulation and metabolism may have potential implication in assessing the safety of these tFA isomers because there is a positive correlation between the intake of tFA and the incidence of various diseases.  (+info)

Trans polyunsaturated fatty acid contents in Brazilian refined soybean oil. (22/153)

This study examined the concentration (mg/g) of trans polyunsaturated fatty acid (TPFA) in five soybean oil brands by gas-liquid chromatography. Tricosanoic acid methyl ester was used as the internal standard. All samples analyzed presented trans 18:2 fatty and trans 18:3 acids in detectable amounts. The concentration of TPFA ranged from 5.8 to 30.2 mg/g, with a mean concentration value of 18.4 mg/g. Trans 18:3 fatty acids had the highest TPFA group concentrations, which ranged from 3.9 to 16.3 mg/g. The main isomer of this group presented the 9c, 12c, 15t configuration. For trans 18:2 fatty acids, concentrations ranged from 1.9 to 14.0 mg/g with a mean value of 8.1 mg/g. Alpha-linolenic acid (all cis) concentrations ranged from 30.7 to 60.6 mg/g and their degree of isomerization ranged from 6.0 to 31.5, indicating that the deodorization process varies from one producer to another. From per capita consumption of soybean oil brands in Brazil and their TPFA concentrations, it is possible to conclude that their contribution to the average TPFA intake per person in Brazil is 0.4 g/d.  (+info)

Plasma phospholipid trans fatty acids, fatal ischemic heart disease, and sudden cardiac death in older adults: the cardiovascular health study. (23/153)

BACKGROUND: Intake of trans fatty acids is associated with increased risk of coronary heart disease. Whether different classes of trans fatty acids show similar associations is unclear. We previously reported an association of sudden cardiac death with red cell membrane trans-18:2 but not trans-18:1 fatty acids. To extend these findings, we investigated the associations of plasma phospholipid trans fatty acids with fatal ischemic heart disease (IHD) and sudden cardiac death. METHODS AND RESULTS: We conducted a case-control study nested in the Cardiovascular Health Study. We identified 214 cases of fatal IHD (fatal myocardial infarction and coronary heart disease death) between 1992 and 1998. We randomly selected 214 controls, matched to cases on demographics, prevalent cardiovascular disease, and timing of blood draw. Plasma phospholipid fatty acids were assessed in blood samples collected earlier. Higher levels of plasma phospholipid trans-18:2 fatty acids were associated with higher risk of fatal IHD (odds ratio [OR] for interquintile range 1.68, 95% confidence interval [CI] 1.21 to 2.33) after adjustment for risk factors and trans-18:1 levels. Trans-18:1 levels above the 20th percentile were associated with lower risk (OR 0.34, 95% CI 0.18 to 0.63). In analyses limited to cases of sudden cardiac death (n=95), higher levels of trans-18:2 fatty acids were associated with higher risk (OR 2.34, 95% CI 1.27 to 4.31) and higher trans-18:1 with lower risk (OR 0.18, 95% CI 0.06 to 0.54). CONCLUSIONS: Higher levels of trans-18:2 and lower levels of trans-18:1 fatty acids are associated with higher risks of fatal IHD and sudden cardiac death. If confirmed, these findings suggest that current efforts at decreasing trans fatty acid intake in foods should take into consideration the trans-18:2 content.  (+info)

Novel soybean oils with different fatty acid profiles alter cardiovascular disease risk factors in moderately hyperlipidemic subjects. (24/153)

BACKGROUND: A variety of soybean oils were developed with improved oxidative stability and functional characteristics for use as alternatives to partially hydrogenated fat. OBJECTIVE: The objective was to assess the effect of selectively bred and genetically modified soybean oils with altered fatty acid profiles, relative to common soybean and partially hydrogenated soybean oils, on cardiovascular disease risk factors. DESIGN: Thirty subjects (16 women and 14 men) aged >50 y with LDL-cholesterol concentrations >130 mg/dL at screening consumed 5 experimental diets in random order for 35 d each. Diets contained the same foods and provided 30% of energy as fat, of which two-thirds was either soybean oil (SO), low-saturated fatty acid soybean oil (LoSFA-SO), high-oleic acid soybean oil (HiOleic-SO), low-alpha-linolenic acid soybean oil (LoALA-SO), or partially hydrogenated soybean oil (Hydrog-SO). RESULTS: Plasma phospholipid patterns reflected the predominant fat in the diet. LDL-cholesterol concentrations were 3.66 +/- 0.67(b), 3.53 +/- 0.77(b), 3.70 +/- 0.66(b), 3.71 +/- 0.64(a,b), and 3.92 +/- 0.70(a) mol/L; HDL-cholesterol concentrations were 1.32 +/- 0.32(a,b), 1.32 +/- 0.35(b), 1.36 +/- 0.33(a), 1.32 +/- 0.33(b), and 1.32 +/- 0.32(a,b) mol/L for the SO, LoSFA-SO, HiOleic-SO, LoALA-SO, and Hydrog-SO diets, respectively (values with different superscript letters are significantly different, P < 0.05). No significant effects were observed on VLDL-cholesterol, triacylglycerol, lipoprotein(a), and C-reactive protein concentrations or on ratios of LDL cholesterol to apolipoprotein B (apo B) and HDL cholesterol to apo A-I. Total cholesterol:HDL cholesterol was lower after subjects consumed the unhydrogenated soybean oils than after they consumed the Hydrog-SO diet. CONCLUSIONS: All varieties of soybean oils resulted in more favorable lipoprotein profiles than did the partially hydrogenated form. These soybean oils may provide a viable option for reformulation of products to reduce the content of trans fatty acids.  (+info)